Preface p. xi Optical properties and applications of ferroelectric and antiferroelectric liquid
crystals
p. 1
Introduction p. 1
Smectic liquid crystals p. 1
Typical molecular structure p. 2
Order parameters p. 3
Point symmetries of the smectic phases p. 4
Ferroelectricity and antiferroelectricity in liquid crystals p. 4
Material properties p. 5
Optical properties p. 5
Dielectric properties p. 6
Mechanical properties p. 7
Alignment p. 8
Homogeneous, homeotropic and pretilt alignment p. 9
Ideal bookshelf p. 10
Chevron formation in tilted smectics p. 10
Influence of pretilt p. 12
Zig-zag formation p. 13
Surface stabilization p. 14
Optical properties of smectic structures p. 15
Optics of simple wave-plate p. 15
Optical properties of chevron structures without pretilt p. 15 Optical properties of chevron structures with pretilt: C1 and C2 states p. 16 Optical properties of antiferroelectric liquid crystal structures p. 16
Interaction with electric fields p. 17
SmA* field response p. 17
SmC* field response p. 18
Simple bookshelf surface-stabilized ferroelectric liquid crystal device p. 18
Effect of the chevron structure in SSFLCs p. 20
Distorted helix effect p. 22
Twisted SmC* effect p. 23
SmC*[subscript A] field response: tristable switching p. 24
Pretransitional effect p. 24
Helical devices p. 25
Surface stabilized devices p. 25
Hysteretic and thresholdless switching p. 26
Displays p. 27
Typical modes of operation p. 27
Grey scale in FLCs and AFLCs p. 29
Spatial dithering p. 29
Temporal dithering p. 30
Display addressing schemes p. 30
Typical FLC and AFLC displays p. 31
Non-display applications p. 31
FLC spatial light modulators p. 31
Electrically addressed SLM p. 31
Optically addressed SLM p. 33
Basic SLM applications p. 35
Telecommunication applications p. 36
2 x 2 fibre optic switch using FLC polarization switches p. 36
1 x N holographic optical switching p. 38
N x N holographic optical switching p. 41
Fabry-Perot type continuous tunable filters p. 42
Digitally tunable optical filters p. 45
FLC-based optical waveguides, switches and modulators p. 47
Optical data processing applications p. 50
Optical parallel processing of binary images p. 51
Optical correlation p. 52
Optical neural networks, ferroelectric liquid crystals and smart pixels p. 55
Other applications p. 55
Photonic delay lines for phased-array antenna systems p. 55
Dynamic arbitrary wavefront generation p. 56
References p. 58
Electro holography and active optics p. 62
Electro holography p. 62
The basics of holography p. 63
Liquid crystal spatial light modulator for electro holography p. 64
Optical characteristics of liquid crystals p. 64
Matrix pixel driving p. 69
Liquid crystal spatial light modulator using MIM devices p. 72 Electro holography using a liquid crystal TV spatial light modulator p. 75
Recording optics and reconstructing optics p. 76
Reconstructed image and its characteristics p. 79
Active optics p. 85
Diffractive optics and refractive optics p. 85
The basics of diffraction p. 85
Liquid crystal diffractive optics p. 88
Liquid crystal refractive optics p. 92
Application to optical pickup p. 96
Optical equalizer p. 98
Coma aberration corrector p. 105
Spherical aberration corrector p. 110
Conclusion p. 115
References p. 115
On the use of liquid crystals for adaptive optics p. 118
Introduction p. 118
Adaptive optics: definition and history p. 120
Image formation: basic principles p. 123
The effect of aberrations p. 126
Active and adaptive optics p. 128
Liquid crystal correctors p. 130
What kinds of LC are of interest? p. 133
Characterization and control of nematic LC devices p. 135
Viscosity and elastic constant p. 135
Thickness of the layer p. 136
Control voltage p. 136
Amplitude control p. 138
Transient method p. 138
Pulse method p. 138
Dual frequency p. 139
Wavefront sensing techniques p. 139
Shack-Hartmann wavefront sensor p. 140
Phase diversity (curvature sensing) p. 142
Putting it all together p. 143
Conclusions p. 146
References p. 146
Polymer-dispersed liquid crystals p. 148
Introduction p. 148
PDLC preparation techniques p. 151
General preparation techniques p. 155
Emulsion technique p. 156
Phase separation techniques p. 157
Polymerization-induced phase separation (PIPS) p. 157
Temperature-induced phase separation (TIPS) p. 158
Solvent-induced phase separation (SIPS) p. 158
Special techniques and materials p. 159
Reverse-mode PDLCs p. 159
Haze-free PDLCs p. 159
Temperature-operated PDLCs p. 159
Phase modulation p. 159
Holographic PDLCs p. 160
Scattering PDLC polarizer p. 160
Gel-glass dispersed liquid crystals (GDLC) p. 160
The physics involved in PDLCs p. 160
LC in confined volumes p. 161
The order parameter p. 161
The free energy density p. 164
Light scattering in PDLCs p. 166
Single scatterer p. 166
A slab of scatterers p. 170
PDLC electro-optical behaviour p. 172
Droplet configurations p. 172
Analytical/numerical approach p. 173
Computer simulation approach p. 174
Multiple-order parameters approach p. 176
Scattering cross section p. 178
Anomalous diffraction approach p. 178
Rayleigh-Gans approximation p. 180
Multiple-order parameters approach p. 181
Applications of PDLCs p. 182
Smart windows p. 182
Heat-resistant PDLC light modulator p. 184
Spatial light modulators p. 185
Direct-view displays p. 188
Projection displays p. 189
Eye-protection viewer p. 191
Sensors p. 192
Holographic PDLCs p. 193
Scattering polarizers p. 194
References p. 196
New developments in photo-aligning and photo-patterning technologies: physics and applications
p. 201
Introduction p. 201
Mechanisms of LC photo-alignment p. 202
Cis-trans isomerization p. 203
Command surface p. 203
Cis-trans transformations in azo-dye side chain polymers and azo-dye in polymer matrix
p. 204
Pure reorientation of the azo-dye chromophore molecules or azo-dye molecular solvates
p. 205
Crosslinking in cinnamoyl side-chain polymers p. 209
Photodegradation in polyimide materials p. 210
LC surface interaction in a photo-aligned cell p. 214
Improvement of materials for photo-aligning p. 214
Pretilt angle generation in photo-aligning materials p. 215
Anchoring energy in photo-aligning materials p. 219
Applications p. 221
Multi-domain LC cells p. 221
Photo-patterned phase retarders and colour filters p. 223
Photo-patterned polarizers p. 228
Security applications p. 233
New developments p. 236
Photo-aligning of ferroelectric LC p. 236
Photo-aligning of vertical aligned nematic (VAN) mode p. 237
Photo-aligning of discotic LCs p. 238
Conclusions p. 239
Acknowledgments p. 240
References p. 240
Industrial and engineering aspects of LC applications p. 245
Practical spatial modulation p. 245
Spatial addressing technologies p. 246
Passive matrix addressing p. 246
Multiplexing addressing p. 247
Active matrix addressing p. 248
TFT active matrix p. 248
LCOS and Si-based matrix p. 251
Two-terminal active matrix p. 252
Alternating field driving p. 252
Charge memory and intrinsic memory p. 255
Longitudinal and lateral field effect p. 255
Optical addressing p. 256
Thermal optical addressing p. 256
Photoconductor addressing p. 256
Other addressing p. 258
Electron beam addressing p. 258
Plasma addressing p. 258
Future aspect p. 259
Amplitude modulation and applications p. 259
Twisted nematic (TN) mode p. 259
Electrically controlled birefringence (ECB) mode p. 260
Guest-host (GH) mode p. 260
Projector application p. 260
Phase modulation and applications p. 260
Active matrix phase modulator p. 261
TFT-driven spatial phase modulator p. 262
Phase modulation characteristics p. 262
Holographic applications p. 263
Kinoform reconstruction p. 263
Interference and diffraction effects p. 263
Spatial wavefront modulator (SWM) p. 265
Optical addressed phase modulator p. 267
Scattering and deflection modulation p. 267
PDLC p. 267
Scattering and Schlieren optics p. 269
Holographic PDLC p. 270
References p. 270
Index p. 273
Abbreviations p. 281
Table of Contents provided by Blackwell's Book Services and R.R. Bowker. Used with permission.
